diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateTime.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateTime.js
index 5b1c26115f..1675371cdc 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateTime.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateTime.js
@@ -29,7 +29,10 @@ describe("correct behavior", () => {
     //       and negative timezones and skip one if we jump the year. To ensure at least one is
     //       tested we have the timeZoneTested which is only set to true if one of the tests passed.
 
-    test("custom time zone positive", () => {
+    // FIXME: The custom time zone tests are disabled due to being flaky. See:
+    //        https://github.com/SerenityOS/serenity/issues/20806
+
+    test.skip("custom time zone positive", () => {
         const calendar = new Temporal.Calendar("iso8601");
         const timeZone = {
             getOffsetNanosecondsFor() {
@@ -53,7 +56,7 @@ describe("correct behavior", () => {
         timeZoneTested = true;
     });
 
-    test("custom time zone negative", () => {
+    test.skip("custom time zone negative", () => {
         const calendar = new Temporal.Calendar("iso8601");
         const timeZone = {
             getOffsetNanosecondsFor() {
@@ -77,7 +80,9 @@ describe("correct behavior", () => {
         timeZoneTested = true;
     });
 
-    expect(timeZoneTested).toBeTrue();
+    test.skip("custom time zone test was executed", () => {
+        expect(timeZoneTested).toBeTrue();
+    });
 
     test("cannot have a time zone with more than a day", () => {
         [86400000000000, -86400000000000, 86400000000001, 86400000000002].forEach(offset => {